diff options
author | Eric Ren <zren@suse.com> | 2017-02-22 15:40:44 -0800 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-02-22 16:41:27 -0800 |
commit | b891fa5024a95c77e0d6fd6655cb74af6fb77f46 (patch) | |
tree | e2d441eb65792f70e2f156f771c4e33949a8731e /fs/ocfs2/acl.c | |
parent | 439a36b8ef38657f765b80b775e2885338d72451 (diff) | |
download | linux-b891fa5024a95c77e0d6fd6655cb74af6fb77f46.tar.bz2 |
ocfs2: fix deadlock issue when taking inode lock at vfs entry points
Commit 743b5f1434f5 ("ocfs2: take inode lock in ocfs2_iop_set/get_acl()")
results in a deadlock, as the author "Tariq Saeed" realized shortly
after the patch was merged. The discussion happened here
https://oss.oracle.com/pipermail/ocfs2-devel/2015-September/011085.html
The reason why taking cluster inode lock at vfs entry points opens up a
self deadlock window, is explained in the previous patch of this series.
So far, we have seen two different code paths that have this issue.
1. do_sys_open
may_open
inode_permission
ocfs2_permission
ocfs2_inode_lock() <=== take PR
generic_permission
get_acl
ocfs2_iop_get_acl
ocfs2_inode_lock() <=== take PR
2. fchmod|fchmodat
chmod_common
notify_change
ocfs2_setattr <=== take EX
posix_acl_chmod
get_acl
ocfs2_iop_get_acl <=== take PR
ocfs2_iop_set_acl <=== take EX
Fixes them by adding the tracking logic (in the previous patch) for these
funcs above, ocfs2_permission(), ocfs2_iop_[set|get]_acl(),
ocfs2_setattr().
Link: http://lkml.kernel.org/r/20170117100948.11657-3-zren@suse.com
Signed-off-by: Eric Ren <zren@suse.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Joseph Qi <jiangqi903@gmail.com>
Cc: Mark Fasheh <mfasheh@versity.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/ocfs2/acl.c')
-rw-r--r-- | fs/ocfs2/acl.c | 29 |
1 files changed, 13 insertions, 16 deletions
diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c index bed1fcb63088..dc22ba8c710f 100644 --- a/fs/ocfs2/acl.c +++ b/fs/ocfs2/acl.c @@ -283,16 +283,14 @@ int ocfs2_set_acl(handle_t *handle, int ocfs2_iop_set_acl(struct inode *inode, struct posix_acl *acl, int type) { struct buffer_head *bh = NULL; - int status = 0; + int status, had_lock; + struct ocfs2_lock_holder oh; - status = ocfs2_inode_lock(inode, &bh, 1); - if (status < 0) { - if (status != -ENOENT) - mlog_errno(status); - return status; - } + had_lock = ocfs2_inode_lock_tracker(inode, &bh, 1, &oh); + if (had_lock < 0) + return had_lock; status = ocfs2_set_acl(NULL, inode, bh, type, acl, NULL, NULL); - ocfs2_inode_unlock(inode, 1); + ocfs2_inode_unlock_tracker(inode, 1, &oh, had_lock); brelse(bh); return status; } @@ -302,21 +300,20 @@ struct posix_acl *ocfs2_iop_get_acl(struct inode *inode, int type) struct ocfs2_super *osb; struct buffer_head *di_bh = NULL; struct posix_acl *acl; - int ret; + int had_lock; + struct ocfs2_lock_holder oh; osb = OCFS2_SB(inode->i_sb); if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL)) return NULL; - ret = ocfs2_inode_lock(inode, &di_bh, 0); - if (ret < 0) { - if (ret != -ENOENT) - mlog_errno(ret); - return ERR_PTR(ret); - } + + had_lock = ocfs2_inode_lock_tracker(inode, &di_bh, 0, &oh); + if (had_lock < 0) + return ERR_PTR(had_lock); acl = ocfs2_get_acl_nolock(inode, type, di_bh); - ocfs2_inode_unlock(inode, 0); + ocfs2_inode_unlock_tracker(inode, 0, &oh, had_lock); brelse(di_bh); return acl; } |